The present subject matter is directed to a system and method for improving speed control of a pitch drive system of a wind turbine. In one embodiment, the pitch drive system includes a direct current (DC) motor having an armature and a series-field winding, a battery assembly having a positive terminal and a negative terminal, and a current-controlling device configured in series between the positive terminal of the battery assembly and the series-field winding. The battery assembly is configured to supply power to the pitch drive system and the current-controlling device is configured to supply current to the series-field winding so as to ensure a field flux does not equal zero. Thus, the current-controlling device has the effect of limiting the maximum speed of the DC motor.

An offshore power generating system has a buoyancy body shaped as a hull with a bow and aft end, and elongated mast extending up from the buoyancy body to the buoyancy body about a horizontal transverse axis. A rotor is supported in one end of the longitudinal mast for rotation about a horizontal axis. The buoyancy body is kept in position with the bow turning up into wind and incoming waves. Rotational support of the mast has a horizontal rotational axis through the center of gravity of the mast that lies in the center plane of the buoyancy body above the aft end when the buoyancy body lies in operational position in calm sea with the rotational axis of the rotational support of the mast orthogonal to the center plane of the buoyancy body. A method for on-board loading and commissioning of mast with installed rotor on-board a buoyancy body.

A method of operating a wind turbine power generating apparatus including a wind turbine rotor having a wind turbine blade includes: a step of obtaining a load applied to the wind turbine blade; and a step of selecting an operation mode of the wind turbine power generating apparatus on the basis of the load, from among a plurality of operation modes including a normal operation mode and at least one load-suppressing operation mode in which the load applied to the wind turbine blade is smaller than in the normal operation mode.

A method is provided for dampening oscillations in a wind turbine, the wind turbine having a tower 1, a rotor 3 arranged on the tower 1 such as to be able to rotate about an X axis, and a plurality of blades 4 with adjustable pitch mounted on the rotor. The method includes monitoring the fore-aft oscillation of the tower 1 in the direction of the X axis, at the 2nd or a higher bending mode frequency; determining a compensating torque to be applied by the rotor 3 to the tower 1 of the wind turbine about a Y axis, which is horizontal and at right angles to the X axis, for at least partly dampening the oscillation at the 2nd or higher bending mode frequency; determining for each rotor blade 4 of the wind turbine an adjustment of the pitch angle suitable to generate the compensating torque about the Y axis; and adjusting the pitch angle β1, β2, β3 of at least one of the individual blades 4 to generate at least part of the compensating torque.

Systems and methods for increasing operational efficiency of wind turbines, especially offshore wind turbines. The invention discloses systems and methods for reducing the torque needed to rotate a rotor shaft axis with respect to the wind direction. Systems and methods for controlling the rotational speed of the rotor shaft axis are also disclosed.

The invention relates to a method for the individual pitch control of the rotor blades of a wind turbine. The method comprises: measuring an acceleration by means of an acceleration sensor in a rotor blade of the wind turbine; high-pass filtering of a signal of the acceleration sensor in order to determine a time-variant variable; and setting the pitch of the first rotor blade of the wind turbine using the time-variant variable, said pitch setting being part of an individual pitch control.

A method for designing a wind energy plant with a generator and with a rotor with rotor blades, comprising the steps determining the size of the wind energy plant which is to be designed, more particularly the rotor diameter and axle height, for a proposed installation site, designing the wind energy plant for a reduced maximum load which is lower than a maximum load which occurs when a 50-year gust strikes the wind energy plant from a maximum loading side.

A control method and a control apparatus of a wind power generator set are provided, in which a wind speed at a location of the wind power generator set is acquired, turbulence intensity is calculated according to the wind speed, and a wind speed distribution range corresponding to the turbulence intensity is determined; a thrust variation amplitude of the thrust in the wind speed distribution range is determined based on a relationship among the thrust suffered by a wind wheel of the wind power generator set, a thrust coefficient and the wind speed; and a maximum rotating speed and a maximum torque of the wind wheel in the wind speed distribution range are adjusted according to the thrust variation amplitude. The maximum rotating speed and the maximum torque makes a fatigue load of the wind power generator set in the wind speed distribution range meet a preset standard.

A shutdown controller for a wind turbine comprises, to improve the estimation of a state of the wind turbine, at least two sensors being adapted to provide sensor data significant for different mechanical states in the wind turbine. The controller can provide an estimated state of the wind turbine based on the sensor data from the at least two sensors and compare the state of the wind turbine with a predefined detection limit to provide a shutdown signal if the estimated state is outside the detection limit.

The current invention relates with a modular gas-heat anti-icing method as well as a device for high-power wind turbine blades, wherein a modular heating system is provided on the blade root, a ventilation duct is provided inside the blade, a wind deflector is provided at the end of the ventilation duct, which divides the front edge of the blade into two parts, so that the hot air in the ventilation duct is only to be conducted to the blade tip and then circulates into the blade root via the rear edge of the blade, enabling the hot air to circulate inside the blade and form a “blade root to blade tip to blade root” closed loop, so that the purpose of heating the front edge of the blade is achieved, and it is ensured that the whole blade does not ice by preventing the front edge of the blade from icing. Using the anti-icing system and method of the present invention, the blades have anti-icing and icing-removal function, which can improve the electricity generation efficiency of the wind wheel in winter. The load of the machine as well as its operation risk has been reduced. The blade is provided with a modular gas-heat anti-icing system, which can be used when the wind wheel is idle, which fills the blank in the state of the art.